Crystallization behavior of isotactic polypropylene/magnesium salt whisker composites modified by compatibilizer PP-g-MAH

摘要

Crystallization behavior of isotactic polypropylene (iPP)/magnesium salt whisker (MSW) composites modified by compatibilizer PP-g-MAH was studied under both isothermal and nonisothermal conditions. Analysis of the isothermal crystallization showed that the Avrami model successfully described the crystallization process. On the basis of Lauritzen-Hoffman theory, a regime transition was observed at about 139 °C for the iPP/MSW composite, and a decrease in the fold surface free energy was calculated with the addition of MSW and PP-g-MAH. The addition of MSW filler and PP-g-MAH compatibilizer distinctly improved the crystallization temperature and accelerated the total crystallization rate of iPP. It was observed that MSW induced the formation of β-iPP but PP-g-MAH suppressed the formation of β-iPP.